The invention relates to a side-channel centrifugal pump having a housing which forms a side channel and whose surface which is adjacent to the side channel forms a front face which is contiguous to the impeller except for a narrow gap, the transition edge from the side channel to the front face being rounded in those regions where it deviates from the circumferential direction, and having an impeller whose vanes have a predetermined web width in the circumferential direction in the front plane of the impeller.
Side-channel pumps are used, inter alia, whenever a high pressure is to be obtained in conjunction with a small conveying flow. A disadvantage of these pumps is the cavitation tendency at those locations on the housing where it has sudden changes in its shape in the direct vicinity of the impeller. Cavitation damage may occur both on the housing and on the impeller. A relatively high level of noise is associated therewith. These disadvantages are particularly noticeable at high rotational speeds, which are understood as being speeds of over 2,800 rpm. Pumps of this type are therefore generally used at a lower rotational speed of around 1,500 rpm.
In the case of the similarly constructed peripheral pumps (DE-A 40 02 027) it is known to provide the transition edge from a wide housing part to the front face of the housing, specifically in the region of the outlet opening, with a rounded portion, in order thereby to reduce the generation of noise.